Base64 File Encoder & Decoder — Any File Type
Encode any file to a Base64 string, or paste a Base64 blob to decode it back to a file. Useful for embedding images in HTML/CSS as data URIs, storing binary data in JSON, or debugging APIs that return Base64-encoded payloads.
Common use cases
Inline an icon in an HTML email as a data: URI, embed a small image in CSS to reduce HTTP requests, or decode a Base64 attachment from an API response back to its original binary form.
Files stay local
Encoding runs in your browser — sensitive files (certificates, PDFs, private images) never touch a server.
Frequently Asked Questions
How big can the input be?
Browser memory limits apply. Files under 10 MB encode instantly; hundreds of MB may stall the tab.
Is Base64 encryption?
No — it's just a text encoding. Anyone can decode it. For secrecy, encrypt first.
Why does Base64 make the file bigger?
Base64 uses 4 characters to represent 3 bytes, so encoded output is ~33% larger than the source.